US1247661A - Method and apparatus for sintering ores. - Google Patents

Description

L' GAYLEY. METHOD AND APPARATUS FOR SINTEBING ORES.

I APPLICATION FILED MAR. 30. I91 m m Patented Nov. 27,1912.

9 SHEETS-SHEET x.

W #7 7, 51 mm. 3 9 WW J. GAYLILY.

METHOD AND APPARATUS FOR SINIERING QRES.

APPLICATION FILED MAIL-30, 191?.

1,241,661 Patented Nov" 27,1911

9 SHEETS-SHEET 2;

w lfoznm ts .l. GAYLEY.

METHOD AND APPARATUS FOR SINTERING ORES. APPLICATION FILED MAR. 30. 1917.

A 1147611 A V Patented Nov. 27, 1917.

9 SHEETSSHEET 3.

| l A HAT-iii! J. GAYLEY. METHOD AND APPARATUS FOR SINTERING oass.

9 SHEETS-SHEET 5- Patented Nov. 27, 1917.

APPLICATION FILED MAR. 30. 19l7- %1 Stab Z140 w"! .I. UAYUZY. METHOD AND APPARATUS FOR SINTERING 0 RES.

APPLICATION FILED MAR. 30. 1917. Patented Nov. 27, 191?.

9 SHEETSSHEET 6.

J'fGAYLEY.

METHOD AND APPARATUS FOR SINTERING ORES.

APPLICATION FILED MAR. 30. 1917.

Patented Nov. 27, 1917.

J. GAYLEY. METHOD AND APPARATUS FOR SINTERING ORES.

' APPLICATION FILED MAR. 30. 19H- L247,661.

Patented Nov. 27, 191?.

9 SHEETS-SHEET 8.

GAYLEY. METHOD AND APPARATUS FOR SINTERING ORES.

. APPLICATION FILED MAR. 30. 19I7. M 661, Patented Nov. 27, 191?.

9 SHEETS-SHEET 9- ens an o,

JAMES GAYLEY, or new vonx, n. r.

METHOD AND APPARATUS FOR SINTERING-OBES.

To all whom it may concern:

Be it known that I, JAMES GAYLEY, a citizen of the United States, residing at New York, county and State of New York, have invented certain new and useful Improvements in Methods and. Apparatus for Sintering Ores, of which the following is a full, clear, and exact description.

The invention upon which is based this application for Letters Patent relates to the art of sintering fine ores. concentrates, waste flue dust or other and similar materials for the purpose of agglomerating the same into sufficiently coherent masses to be available for economical use in blast furnaces. The invention involves a new method as well as an improved apparatus for the practice of this art, the object being to provide for the treatment of the material by a continuous sintering operation, and to produce an apparatus, for the purpose more simple and economical in operation than those heretofore used and adaptable, without material change, for small or for large tonnages of output.

Materials of any description of the general class above referred to may be treated by the method and apparatus of this invention, whether they contain, in themselves,

sufiicient fuel for sintering or only a portion of that necessary, or none at all, as where there is any deficiency in the fuel, it is preferably supplied by the admixture therewith of carbon in some available form. The supply of iron ores, for example, is gradually becoming leaner, but there are large mag netic ore formations containing from 30% to 40% of iron, which can be beneficiated by concentrating'processes to produce a very rich grade of ore, but generally too finely subdivided in character for use in blast furn aces, and thesetherefore have to be agglcme'rated and preferably, by sintering such as is effected by the present invention.

The beneficiation of the lean ores however, must be carried out on a large scale to be profitablev and this, in turn, requires sintering plants of large capacity, which preferably avoid the duplication of small units, and the multiplicity of machinery. equipment, and movingparts. These objects I Specification of Letters Patent.

Application filed March 30, 1917. Serial No. 158,652.

accomplish by new methods and arrangements and by the adoption of a desi simple and more economical in construction and operation, and by means of which a continuous sintering operation may be carried out in which the cars or receptacles for containing the material are in constant use and substantially uniform motion, throughout the sintering operation, all parts of the apparatus being under proper control and so arranged that a continuous bed or beds of material to be sintered is provided and treated.

Materials that require sintering at the present time vary widely in their requirements with respect to treatment. Some, for example, are sintered to the best advantage in layers of a thickness of four or five inches, while others are preferably treated in layers of several feet, even up to four or five feet in depth.

In practising the continuous processes now in common use, in which the cars or pallets travel in one direction over one track and are returned idle in the reverse direction on another and usually a lower track, it is not desirable to use pallets of materially larger grate area, as their weight would be greatly increased, and the shock of such pallets, dropping at the discharge end of the machine would be destructive of the metal surfaces, and it is obvious that it would not be practicable to treat on such machines sintering layers that may vary in the character of materials so as to require widely varying thicknesses, as the mechanism provides no flexibility of this wide range of service.

-The average charge now treated on a con- .tinuous machine 1s about 7 inches, but for the treatment of layers several feet thick,

the cars become too heavy and unwieldly and present many mechanical difficulties in their operation around the curved end tracks. In my system, however, the sides of the cars may be of any height desired for the best practical results without necessitating any substantial changes in the deslgn or construction of the plant as a whole.

I am also able to provide a continuous process of sintering which will greatly reduce the number of idle cars, rendermg thereby each in use more eifective in the production of output and making it possible to eal he. ars n e for e te ing eir "travelfrem one end of anneal to the r cks us g hi t rm it ede sca in *s't'ibstantually the same horizontal plane,

over which the cars are adapted tobemoviad uniformly and continuously in reverse directions. Having reached the. discharge end ofi 'atra'clc each car is emptied ofitssintered contents, transferred in. any suitablemanner to the return track, refilled with ore or other material which is then ignited and sintered during the passage; of-the ear to its original starting oint, where it is again. dumped, refilled caused totravel in the reverse direction overthe first track;

. This process calls for certainstructural and functional features new to. machines of this class,. and these. will be more fully set forth in the detailed description of the annexed drawings. which follow.

In the drawings Figures 1 and 1 show a side elevation. the complete system or apparatus. which. I have. devised for carrying out my invention.

Figs? and 2% are views in plan offthe same denicesi 1 Fig. 3 is an enlarged sectional view" of; a portion of. the lettha-ndend of'iFig. ,1. .r Fig; 4. isan enlarged view in; elevation of a combined. means.- fordumping; the cars of their sintered contents, and transferring the empty cars to another track.

Fig. 5 is an end view in elevation ofthe apparatus shown in the above figures.

Fig. -6 is=an enlarged view in elevation .of the end portion of the apparatus showing the. means tor disconnecting" the cars from the tram and other features:

Fig. 7- is? a cross-section on. are enlarged scale ofiasintering car.

Fig. 8 isa view in elevation andpa-rt sec? tionofa portion of the trainoicars Fig 9*1s a; sideviw in-elievatinn eta modifiediorm of'the-apparat'us.

, Fig. 1 0 v is asimilar view of. another por tionof the same, and- Fig. 11 a plan view or; apartof the same form'of! apparatus illustrated in-the two preceding figures. r

Theapparatusds designed to be=supported by suitable framework 1 which-,as. shown in Figs. 2 :and 2' comprises two: substantially parallel tracks, 2; and 3 upon which-trains of cars dare-adapted to travelin one: direetion 1 oneach .traek.

' It-is-not necessary to describe-in great de tfiilithevprorisions Y that ar'e'made. for; sintering the contents of the cars as they. pass over these tracks, as these are clearly shown in the drawings, and are wellknown in the art, being co'mmonlyjin apparatus of this general character. Suflicient to say, that at the receivin end of each track there is pref- "cra'bly, a s ort' incline 5, onto whichthe ars, 3.116 pushed .by a piston pusher 6, or any 7 other suitable means, and down which they run into engagement with a power drive represented by the chain and sprocket wheels '7, 8, which engages the car and propels it with the train ahead of it over the tracks with a uniform. and continuous movement.

The thus far described may, as it will be understood, be of any known or suitable kind adaptedyfor their purpose.

The-cars are moved forward over the dead plate 9, and under a feed hopper 10, which contains the material. tobe sintered, and from these hoppers the material is fed onto the cars or-thebedwhiclrthey provide, the rate of:-feed beingadjusted to the speed-of movement ofthe cars to secure the properdepth' of-layersor charge. As the cars pass beyondthe feed' hopper the'top of the charge or layer of material thereon is surfaced or smoothed'by a brush or dra 11: I

The carnext moves -un er an ignition furnace or other'equivalent device 12, which by means of a hot; flame o'fburnin gass'or .011 ignites the topsurface of the smtering layer, and from thi's point on1 to theend of 1 its line-of travel apparatus by which the cars are handled andqthe actions-to which I the sintering' material is subjected differ in no essential respect fromthose heretofore employed. In other words when a car comes underthe igniter it passesko'ver the wind'box 13, which maintains a draft down. through the material and can grate during its-course over thetrack: until it is v sufilciently and'properlysintered. As power 4 fan 14: is-conneotedwith the suctionohamber' 025- the wind box which: draws down: through the 'sinteringmassthe gases of combustion and any intermixed airanddischarges them into a-chimneyz After a can has traveled along the track and ov'er the wind-box for the proper distance to secure-the proper-and desired sinterin A of its -contents,--this1 being. also detenmmed by the speed of travel according to the.- eharacter-and amount of them'at'erial, i passes over-a second terminal dead plate 9*, Figs. 1c and 6,. which shuts'ofi' the suction of air through: its contents and is engaged by: a power drive 150i anysuitable character, which accelerates its speed of movement and delivers it to the dumping cradle-16. The drive 15, preferably moves the cars at a higher rateof speed than the .maindrive 7, in order that after the charge is simemed .the car, centnining; it. may; be

moved ofi', dumped and again put in service with the least possible delay. The acceleration of speed may be secured or facilitated by giving to the portion of the track 17 beyond the dead plate a suflicient decline for the purpose, and'this is not so desirable in case the cars are very heavy.

The dumping apparatus may be of any p'ropercharacter designed to receive a car and to overturn it in order to discharge its contents. In Fig. 4 such devices are illustrated for convenience and shown as consisting of a combined dumping and transfer carriage composed of a circular cradle 18, mounted between four supporting rollers 19, all carried by a transfer carriage 20. When a car runs into the cradle it is securely held against lateral movement, and the car dumping frame 18 normally rotated to dump its contents into a chute 21, discharging into cars 22 and 23, that carry off the agglomerated mass passing over grizzly bars 32 or the fine particles screened through these grizzly bars.

After a car is dumped, it is carried by the transfer car 20, up an inclined track 24, and brought into line with and preferably somewhat above the level of the return parallel track 3, as shown in Fig. 2. From this position in line with track 3, it is immediately advanced by a piston pusher 6 on to the track, refilled, and its contents ignited and then moved over a wind box in a second sintering operation in precisely the same manner and by apparatus of the same character as above described.

In Fig. 2 there is shown an additional track 25, at right angles to the transfer track 24, which is used as a repair track. A piston or pusher 6 is arranged opposite this track to force cars thereon, from whence they may be removed by a traveling crane at 26, should occasion require. There are also at the sides two sintering tracks 27, 27 for material cars.

By far the largest proportion of materials which are sintered at the present time by the continuous process, rarely require for the best operative results a depth or layer in excess of nine inches, consequently, the sides of the cars or pallets are made low, and they have no-upright ends at all. The cars are also carried on wheels that run on the tracks provided for that purpose, and at both ends they are so constructed or planed oif that they will make tight joints when brought together in a train to prevent the leakage of air. It is further usual to provide on the sides of the cars wind seals 29, Fig. 7, preferably composed of single bars free to move vertically in a slot in the car body and slide over the edges of the wind box. In the process of sintering herein described, the cars, it will be observed, are always held in an upright position, so that this or many other forms of wind seal may easily be ap plied and used.

The advantage of using cars without upright ends follows from the fact that this provides for the operation being carried on as a strictly continuous one. cars are dependent in the sense that their ends contact to make close air tight joints throughout the sintering train. The layer of sintering material which such cars support is, moreover, continuous, or uninterrupted throughout the sintering period. From this it results that the ignition of the layer is more uniformly and effectively performed, and carried out while the cars are in motion. When independent cars with side and end walls are used the ignition of the charge takes place under a hood the cars having the side and end walls of equal height to prevent leakage of the ignition flame, and it is required that each car remain stationary while the ignition of its charge is taking place.

These stoppages of each car, in turn, stop the whole train and thereby render the process an intermittent one, curtailing the sintered output and imposing a variable load upon the suction fans through the variations in the percentage of the total sintering bed from time to time, thus producing at difierent times a variable suction pressure in different parts of the same, but disconnected sintering bed.

The material which lies against the sides and ends of independent cars is, moreover,

not so perfectly ignited, so that the elimination of ends reduces the area of imperfect ignition. Besides. the car-with side and end walls makes the sintering layer disconnected, and it is not practicable to properly ignite a moving layer which may vary considerably in depth. For effective and economical ignition, the igniter must be close to the moving layer to produce the required heat concentration, but if for any reason a change occurs in the character of the material to be sintered, and a varying depth of the layer is required, it is not possible with independent cars to properly adjust the height of the igniter above the layer as this is limited by the ends of the cars which must pass under the igniter and in consequence the ignition and sintering of the layer is imperfect.

In treating the same kind of material in a connected or continuous layer, the igniter can be placed in a fixed and proper position for that material and remain in such position, and this fact permits the use of a gas of low calorific power such as blast furnace gas, while intermittent ignition under a hood requires a high calorific and much more expensive gas.

The several exactly its capacity for the existing condi- .tions.

In slnterlng operatlons where 1ndependent cars are used and the charges ignited under a hood, the charging of the cars and the ignition of the material become manual and intermittent operations, Whereas in the method or process as herein described, the

only manual operations involved are the dumping and the transferring of the cars.

When materials are used that require a .considerable depth of sintering layer a somewhat modified form of car is desirable to better meet the practical conditions encountered. When a charge, for example, in a car is fully sintered and has passed beyond the-dead plate, the break between the sintered sections of layer on adjoining cars is easily effected if the layer be thin, but not so if thick. For thick layers, therefore, it is preferable to construct the cars with end walls, but of less height than the depth of the layer, so that the latter is continuous over the car ends to make an uninterrupted surface layer, but partly separated below by the car ends. This modification provides the same continuity of filling, igniting and operation as with a lesser depth of layer on cars without ends. The car ends just described are designated 30, in Fig. 8. a

, In order to sever sections of the continuous sintered layer at the proper points over the contact line of two adjoining cars, I prefer to drop each car after it has passed over the dead plate a sufficient distance to break the layer. For this purpose that portion of the track marked 31 in Fig. 6 is set below the level of the remainder, so that as each car comes upon this lower section its superincumbent layer is broken.

The gas with any intermixed air that is drawn down by the fan through the sintering charge and the grates supportin it, passes into the suction chamber 13, w ich is preferably made of the full width of the grates so that the suction pressure will act reely and equally upon the entire sintering charge; there being no restriction in area from the bottom of the grates to the point of outlet to the conduit which leads to the fan or blower. I thus maintain a continuous, unrestricted and capacious suction chamber under the whole train of cars undergoing the sintering action. Like the other functions of the apparatus, the gas withdrawal is in continuous, uniform and connected flow from the grates to the exit from the suction chambers. This results in im osing a uniform load on the fans and e ects economy of power, and enables me to secure an accurate indication of suction for a bed of any specific material. I therefore avoid irregularities of sintering by dispensing with restrictions in outlet which cause unequal suction, as the line of least resistance to the gas flow is the grate area section directly above the restricted opening, and the greatest resistance is at points farthest removed. A restricted gas outlet makes a sintering unit of each car, whereas by my construction I make a single sintering unit of all the active cars in the serles.

When the sintered material is discharged from the car in the dumper, it falls, as above the car 22.. Similarly at the point where the sintering cars drop to break the sinterbed, the material broken off from the disconnected sections of layers falls into a hopper from which the larger pieces pass through a chute 34 into car 36, and the finer particles through a grizzly and a chute 35, into a car 36. In both cases the fine material is returned to the system and mixed with the'raw material, serving the useful purpose of imparting greater permeability to the sintering charge, and benefiting the quality of the sinter.

By having a large and unrestricted suction chamber, the dust that is drawn down from the charge is deposited more readily and less dust passes over to 'cut the fan blades. The dust that is collected is removed through the conduits 37, and "returned in car 23 to raw material for further treatment.

In Figs. 9, 10 and 11 I have shown a modification of the plan above proposed which has the merit of greater simplicity, and may, in many cases, be preferred to that described. In these figures the apparatus as a whole is substantiall the same as in the preceding parts of the drawings, but the means for dumping are not combined with the transfer carriage in one device. In other words, the cars with their sintered contents are carried up a slight incline 38 and then caused to run over a decline into the dumping device 18 from which after being overturned they are pushed on to the transfer carriage 20 and carried empty over a horizontal transfer track to the receiving end of track 3 which, as shown, is slightly declined, so that when the car is pushed onto it it will run down into engagement with the power drive. The relative merits team by those skilled in this art.

A further modification which would still retain many of the important features of my lmproved method and apparatus is pos sible in cases where the production of a large output is not demanded and where economy in the construction of the plantis acontrolling consideration. Such modificat on consists in dumping the cars with their slntered charges and then returning them to the receiving end of .the track empty instead of filled and quickly instead of slowly as would be required if they contained charges to be sintered during their return Journey. These and many other modifications can conveniently be made without departure from the spirit of the invention.

By the above described method of sintering the cars are kept in practically constant slnterlng service, and a large number of idle cars avoided which the use of the upper and lower tracks in the more ordinary systems involves. It will be seen that the construction of the apparatus is exceedingly simple and easily operated and carries out the process of continuous sintering in a new and efficient manner. By the use of two independent and correlated sintering tracks, the

cars, after being discharged from the end of one track, are lmmediately used as units in another sintering operation on the return journey and prior to being passed again onto the original track. This represents an increased use of grate area for a given comblnation of parts and requires less grate area than it is necessary to provide in plants now designed for the continuous process of sinter ng.

The advantages of the invention will be appreciated by those skilled in the art. I conduct a continuous process of sintering by means of an apparatus, substantially all parts of which move horizontally, thus making the design strong, simple and flexible, with a lower mechanical maintenance than is true of any others now in use. ll obtain more useful sintering action from the car equipment, and can use cars of any length, width or depth of side within the limits of good mechanical practice, with only slight changes of design and plan.

I am enabled to treat awide variety of materials in layers greatly varying in depth and maintain a connected layer over moving cars, securing thereby the advantage of continuous operation, and produce large outputs at small cost of operation in a plant that is compact, adaptable and simplified in construction. I provide an apparatus that enables the operator to observe the quality of sinter being made in a cross section of the layer, which is necessary to effective and workmanlike control.

in connection with my sintering improve- I ments, but reserve the same for a separate application for Letters Patent in my name.

What I claim is:

1. The method of sintering fine material by a continuous operation, which consists in forming a grate-bar platform for a con nected layer of material by a train of abutting cars; moving the same, after the material thereon has been progressively ignited, over the suction chamber and progressively sintering the same; severing the layer of sintered material at the lines of junction between the successive front cars of the moving train and the next adjacent cars in rear; moving in a substantially horizontal plane the successive cars with the material overlying the same severed from the.connected layer at an increased rate of speed from the train, to successively advance each of the thus-severed cars out of contact with those which follow it; and successively tipping the thus-advanced cars to dump the material overlying them while out of contact with preceding cars.

2. The method of sintering fine material by a continuous operation which consists in forming a continuous grate-bar platform for the material by a series of abutting cars, moving the same, after the material thereon has been progressively ignited, through the machine and dropping the cars without changing their upright position at the end of their travel a sufiicient distance to break ofi' the overlying sections of sintered material from the mass and then dumping the broken off sections.

3. The method of sintering fine material by means of two trains of dependent cars forming continuous grate-bar platforms for the material to be sintered and moving in a substantially horizontal plane, breaking off the continuous layer of sintered material at the junction line of two abutting cars, dumping the cars when the overlying material is thus broken, and maintaining them at all other times throughout the cycle of operations in an upright position.

4:- In a sintering apparatus, the combination with a train of dependent cars forming an uninterrupted bed for the sintering material, means for moving said cars under an igniter and over a wind box and means for dropping each car without disturbing its upright position at the end of its line of travel a sufiicient distance to break the overlying connected sintered layer.

5. A sintering apparatus adapted for continuous operation comprising parallel tracks in substantially the same horlzontal plane; two trains, one for each track, composed'of dependent abutting cars forming a continuous grate platform for the material to be sintered, and means for moving said trains simultaneously in opposite directions on said tracks; means for depositing the material to be sintered upon said grate platforms in the form of a continuous layer; a maintained flame for igniting the sintering material While in motion; means for breaking 10 the continuous layers of sintered material at the junction line of two abutting ears in said trains; means for dumping the cars containing the thus-broken portions of said layers; and means for transferring the dumped cars from one track to the other 15 the ears being malntained in upright position at all times except While being dumped. In testimony whereof I afiix my slgnature.

JAMES GAYLEY.

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